Application of Cimatron E in Injection Mold Design and NC Machining Programming

Cimatron E numerical control programming consists of three important parts: 3D modeling, tool path design, tool path editing and modification, machining simulation, post processing, NC programming template, secondary development function interface, data file exchange and so on. The system provides point machining programming functions such as drilling, tapping and boring cycles. It has a variety of contour machining, contour cutting and cutting and island machining plane milling programming. It provides 3~5 coordinate complex surface multi-axis linkage machining programming function, with multiple tool path control based on residual blank, surface contour, contour stratification, surround equidistance, curved streamline, corner clearing, curve five axes, etc. the way. The main machining strategies for tool path include parallel milling, wrapping, contouring, deep hole drilling, roughing based on various forms such as blanks.

Cimatron E provides mold milling machining programming that is simple and convenient, and absorbs the advantages of CNC programming functions of other CAD/CAM systems. System-rich three-axis rough machining combined with intelligent cutting based on residual blanks, control of high-speed cutting trajectory, coarse-finishing of forward rake and roll angle of 5-axis controlled tool axis vector, rapid drilling, and roughing With the programming function, the CNC machining program of the product can be completed quickly and efficiently. For each machining strategy, there are many control methods for tool path generation. For the machining of large-volume pockets and space surfaces, the tool path is controlled by: Stock Spiral based on residual blanks; Parallel cut of space surface, its trajectory is parallel to a straight line on the XY plane; a point on the plane is the center of the circle, and the trajectory is radially processed in the radial direction (Radial); contour layer milling (By Layer) ); 3D Step of the surface contour; 3D Step; the contour of the trajectory along the contour of the surface is fixed in the XY plane of the Z-axis. Profile; deep hole drilling roughing displacement (Plunge Mill ); space curve triaxial or five-axis machining (Curve 3x & Curve 5x). The typical tool path control strategy is shown in Figure 7.

1. Cimatron E CNC programming basic process

Since the system interface is designed strictly according to the CNC machining process of the actual product, its operation is simple. During the entire tool path design and planning process, the machining object, cutting parameters and other contents can be arbitrarily modified. It is worth noting that due to its correlation, When designing a tool path, it is best to have a general plan for the definition of the machined object. It can copy, paste, delete and hide the tool path and machining program. At the same time, it can edit and modify the specific tool path plan, such as the following knife and corner speed adjustment. The system NC machining programming module provides the following functions: Observing the movement of the tool along the trajectory in the graphical mode, and performing graphical modification; having the function of copying, editing, modifying, tool definition, machine tool and cutting parameter database of the tool position file, such as The tool path is extended, shortened, trimmed, and so on.

Cimatron E is used for CNC machining of product parts. The flow is shown in Figure 8. The first is to call the product part to load the blank, call the system template or user-defined template, design the tool. Then, the machining program, the definition operation, the machining object, and the machining method are respectively created to generate the corresponding machining program. The user establishes the tool path generation method according to the content of the machining program. For example, according to the specific content of the machining object, the tool guiding mode, cutting step distance, spindle rotation speed, feed amount, cutting angle, advance and retreat cutting point, interference surface and safety The tool path is generated by details such as plane. After the tool path is simulated and processed, the corresponding editing, copying and copying operations are performed to improve the programming efficiency. After all the tool path design is qualified, post-processing is performed to generate the machining code of the corresponding CNC system for DNC transmission and CNC machining.

2. Mold NC programming template

The use of CNC programming templates facilitates the use of existing experience and expert knowledge to achieve the purpose of sharing resources within the enterprise. The system provides the machining program template, tool template, machining object template, tool path template and so on. In the template, the knowledge, experience and habits of CNC programmers, processing technicians and skilled workers are continuously injected, and the standardized CNC machining process is established, which lays a good technological foundation for strengthening the production management and improving the processing efficiency and quality of the products.

Cimatron E system creates user's own template to set the pre-processing sequence, process parameters and cutting parameters. For similar parts processing objects, applying templates can greatly improve the efficiency and quality of CNC programming, especially in the mold industry. Users can easily obtain expert-level manufacturing process guidance from templates through the machining wizard. The entire content can be easily and effectively provided to inexperienced users, which is beneficial to absorbing other people's experience. Through the wizard, pre-defined templates can be activated and quickly generate CNC machining tool tracks with simple interaction. The machining program template and the tool path template are saved in file formats of *.pct, *.tpt, and *.mtt, respectively.

3. Variable speed cutting and based on residual blank cutting

The Cimatron E system provides the same volume constant-speed variable-speed cutting function, which is especially suitable for the cutting of difficult-to-machine materials with large machining allowances on ordinary CNC machine tools, so as to give full play to the performance of tools and machine tools. Since the proportion of ordinary CNC machine tools in existing enterprises is still large, the tool path strategy using variable speed cutting can reduce the manufacturing cost and improve the processing efficiency. Figure 9 shows the variable speed cutting function settings provided by the system. CimatronE's high-speed milling capabilities support contoured roughing and surface finishing, avoiding 90 by rounding corners at corners. Sharp turn (high-speed occasions are easy to damage the guide rail and motor), and adopt the screw advance and retract knife with the automatic adjustment function of the feed speed, which is very suitable for high-speed cutting. The system also provides various methods such as surround equidistance to support high-speed machining tool path. Generate a strategy. With the programming function based on residual blank cutting, the software automatically eliminates empty tool paths, reducing the user's workload and improving programming efficiency.

As shown in Fig. 10, on the CimatronE platform, the tool path of the hot stamping die cavity and the core CNC milling program of a composite product product is fully utilized by the system numerical control programming template and the equal volume variable cutting function.

Sixth, the conclusion

Cimatron E is a very versatile CAD/CAM integration software that is ideal for the development and processing of a wide range of molds. This article is only the most basic applications. I believe that with the familiarity and application of Cimatron E, we will find more and more powerful functions. I hope this article can play a role in inspiring.